A hospital struggling to meet waiting time targets is “under even greater pressure than we first thought” according to an MP after a watchdog revealed medical staff were not keeping proper notes.

The National Audit Office (NAO) reported hospitals across the UK are failing to maintain accurate records before treatment for more than half of their patients and said it identified The North West London Hospitals NHS Trust, which runs Northwick Park Hospital in Watford Road, Harrow, had “mis-recorded data” for the waiting times of 2,700 of those receiving planned inpatient treatment, equivalent to 60 per cent of the total.

The hospital had already come under fire for failing to meet Department of Health targets for starting elective, consultant-led care treatment within 18 weeks of a patient’s referral, usually by their GP.

Labour MP for Harrow West Gareth Thomas said: “The recent data published by the NAO suggests that patients are having to wait longer than people were led to believe.

“It appears that Northwick Park Hospital is under even greater pressure than we first thought.

“This underlines the concerns of the impact of closing Central Middlesex and Ealing Hospital A&E departments could have on residents in Harrow.”

The closures mentioned by Mr Thomas are in the pipeline as part of NHS North West London’s Shaping A Healthier Future shake-up of acute healthcare in north-west London.

Chief executive of the hospital trust, David McVittie, said: “We were already aware of the issues raised prior to the National Audit Office’s report.

“We identified problems with our systems and processes last year and acted immediately.

“We have overhauled our processes and systems to prevent this happening again and I apologised to those patients affected at the time.

“We have established an investigation panel, led by an external clinician, to provide us with further assurances that the situation has been fully resolved. The panel is due to report to the trust in March.”

The NAO said its report was based on a review of 650 orthopaedic patient waiting times across seven trusts and said it found 12 North West London Hospitals NHS Trust patients who had waited more than a year for treatment.